Rock Identifier

Category

Mineraloid (Human Made Geological Specimen)

Browse mineraloid (human made geological specimen) specimens identified by the Rock Identifier community.

Basalt (Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)) — Igneous

Basalt

Mafic volcanic rock (primarily plagioclase feldspar and pyroxene)

Rose Quartz (Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese) — mineral

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Geode (Unbroken) (Silicon Dioxide (SiO2) usually as Microcrystalline Quartz or Chalcedony) — sedimentary

Geode (Unbroken)

Silicon Dioxide (SiO2) usually as Microcrystalline Quartz or Chalcedony

Quartzite (Sugar Quartz) (Quartzite (primarily SiO2)) — metamorphic

Quartzite (Sugar Quartz)

Quartzite (primarily SiO2)

Porphyritic Basalt (Porphyritic Basalt (with Plagioclase phenocrysts)) — igneous

Porphyritic Basalt

Porphyritic Basalt (with Plagioclase phenocrysts)

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Fossilized Coral (Petoskey Stone or similar) (Hexagonaria percarinata (Order: Rugosa)) — sedimentary

Fossilized Coral (Petoskey Stone or similar)

Hexagonaria percarinata (Order: Rugosa)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Blue Chalcedony (Silicon Dioxide (SiO2)) — mineral

Blue Chalcedony

Silicon Dioxide (SiO2)

Green Chalcedony (likely Chrysoprase or dyed Green Agate) (Silicon Dioxide (SiO2) with nickel impurities or chromium/dye) — mineral

Green Chalcedony (likely Chrysoprase or dyed Green Agate)

Silicon Dioxide (SiO2) with nickel impurities or chromium/dye

Obsidian (Obsidian (Volcanic Glass)) — igneous

Obsidian

Obsidian (Volcanic Glass)

Basalt (Basalt (Aphanitic Mafic Igneous Rock)) — igneous

Basalt

Basalt (Aphanitic Mafic Igneous Rock)

Placer Gold Nugget (Native Gold (Au)) — mineral

Placer Gold Nugget

Native Gold (Au)

Jasper (Red Jasper) (Silicon Dioxide (SiO2) with Hematite inclusions) — sedimentary

Jasper (Red Jasper)

Silicon Dioxide (SiO2) with Hematite inclusions

Red Jasper (Jasper (a variety of Chalcedony, SiO₂ with impurities)) — Mineral

Red Jasper

Jasper (a variety of Chalcedony, SiO₂ with impurities)

Alexandrite (Chrysoberyl (BeAl2O4 with Chromium impurities)) — mineral

Alexandrite

Chrysoberyl (BeAl2O4 with Chromium impurities)

Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony) (Chert (microcrystalline quartz)) — Metamorphic Rock

Banded Chert / Banded Jasper (likely a variety of Chert/Chalcedony)

Chert (microcrystalline quartz)

Metamorphic Rock

Gastropod Steinkern (Fossil Snail Internal Mold) (Class Gastropoda (Internal Mold)) — sedimentary

Gastropod Steinkern (Fossil Snail Internal Mold)

Class Gastropoda (Internal Mold)

Geode (Quartz chalcedony variety) (SiO2 (Silicon Dioxide)) — sedimentary

Geode (Quartz chalcedony variety)

SiO2 (Silicon Dioxide)

Libyan Desert Glass (Impactite (High-silica tektite)) — mineral

Libyan Desert Glass

Impactite (High-silica tektite)

River Pebbles (Tumbled Quartz and Basalt) (Silicon Dioxide (SiO2) for white quartz; Mafic Volcanic Rock for basalt) — igneous and sedimentary

River Pebbles (Tumbled Quartz and Basalt)

Silicon Dioxide (SiO2) for white quartz; Mafic Volcanic Rock for basalt

igneous and sedimentary

Horn Coral Fossil (Rugosa (Order Rugosa)) — sedimentary

Horn Coral Fossil

Rugosa (Order Rugosa)

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Quartz (Milky/Smoky variety) (Silicon Dioxide (SiO2)) — mineral

Quartz (Milky/Smoky variety)

Silicon Dioxide (SiO2)

Blue Sea Glass (Amorphous Silica (Anthropogenic glass)) — not a rock (man-made origin)

Blue Sea Glass

Amorphous Silica (Anthropogenic glass)

not a rock (man-made origin)

Aquamarine (Beryl (Be₃Al₂Si₆O₁₈), specifically a blue or cyan variety) — Mineral

Aquamarine

Beryl (Be₃Al₂Si₆O₁₈), specifically a blue or cyan variety

Andesite Porphyry (Andesite (Intermediate Volcanic Rock)) — igneous

Andesite Porphyry

Andesite (Intermediate Volcanic Rock)

Scoria (Lava Rock) (Scoria (Vesicular Basaltic Rock)) — Igneous

Scoria (Lava Rock)

Scoria (Vesicular Basaltic Rock)

Scoria (Vesicular Basalt) (Vesicular Basalt) — igneous

Scoria (Vesicular Basalt)

Vesicular Basalt

Basalt (Extrusive mafic igneous rock) — igneous

Basalt

Extrusive mafic igneous rock

Chert (Jasper or Flint variant) (Chert (composed of microcrystalline quartz, SiO2)) — sedimentary

Chert (Jasper or Flint variant)

Chert (composed of microcrystalline quartz, SiO2)

Quartz with Iron Staining (Silicon Dioxide (SiO2)) — mineral

Quartz with Iron Staining

Silicon Dioxide (SiO2)

Smoky Quartz (Silicon Dioxide (SiO2)) — mineral

Smoky Quartz

Silicon Dioxide (SiO2)

Sandstone (Fossiliferous) (Clastic Sedimentary Rock (primarily SiO2)) — sedimentary

Sandstone (Fossiliferous)

Clastic Sedimentary Rock (primarily SiO2)

Sandstone (Arenite (Siliclastic Sedimentary Rock)) — sedimentary

Sandstone

Arenite (Siliclastic Sedimentary Rock)

Quartz (Variety: Rock Crystal Cluster) (Silicon Dioxide (SiO2)) — mineral

Quartz (Variety: Rock Crystal Cluster)

Silicon Dioxide (SiO2)

Celestine (Celestite) (Strontium Sulfate (SrSO4)) — mineral

Celestine (Celestite)

Strontium Sulfate (SrSO4)

Unakite (Epidotized Granite (SiO2 with Ca2(Al, Fe)3(SiO4)3(OH))) — metamorphic

Unakite

Epidotized Granite (SiO2 with Ca2(Al, Fe)3(SiO4)3(OH))

Conglomerate (Clastic Sedimentary (Conglomerate)) — sedimentary

Conglomerate

Clastic Sedimentary (Conglomerate)

Sandstone (Arenite) — sedimentary

Sandstone

Arenite

Milky Quartz (Silicon Dioxide (SiO2)) — mineral

Milky Quartz

Silicon Dioxide (SiO2)

Granite (Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)) — Igneous

Granite

Granite (a common rock type, not a single mineral; composed primarily of Quartz, Feldspar (Orthoclase and Plagioclase), and Mica (Biotite and/or Muscovite) and/or Amphibole)